The T25FW is a quantitative measure of lower extremity function in persons with multiple sclerosis. The T25FW was the primary outcome measure of efficacy used in MS studies of dalfampridine and is being performed in our study as a means of comparing results across studies and populations. The T25FW can be measured during the 10MWT.

The WISCI II is a walking scale specifically developed for use in clinical trials in persons with incomplete SCI. Walking ability is scored on a 21-point ordinal scale (0-20, where 0 indicates a person is unable to stand and/or participate in assisted walking and 20 indicates a person can walk more than 10m without walking aids or physical assistance), where a lower number indicates higher impairment.

The SCI-FAI is an observational gait assessment instrument that addresses three key domains of walking function in individuals with SCI. The three SCI-FAI subscales are Gait, Assistive Device, and Walking Mobility. Parameters of the SCI-FAI are measured during the first 2 minutes of the 6MWT (see above).

The LEMS measures strength in five muscle groups bilaterally (hip flexors, knee flexors and extensors, and ankle dorsiflexors) with the modified British Medical Research Council scale and is performed during the International Standards examination.

Spasticity assessments will be performed at each study visit using the modified Ashworth scale (MAS). Ashworth scores will be averaged across three muscle groups bilaterally: hip adductors, knee extensors, and knee flexors. The Ashworth Scale data will be collected on a 1-5 scale rather than the published 0-4 scale.

The bladder management questionnaire uses a 6-point scale and requires the subject to rate the frequency (0, "Not at all"; 5, "Always or almost always") of eight items regarding bladder management over the past month.

The FSFI is a multidimensional, self-report instrument used to assess female sexual function. Six domains are identified that include desire, subjective arousal, lubrication, orgasm, sexual satisfaction, and pain.

The ISCIPDS:B contains core questions about clinically relevant information concerning SCI-related pain that can be collected by health-care professionals with expertise in SCI in various clinical settings. Each person is asked to describe the three worst pain problems he/she is currently experiencing.

The SCIM is a measure of functional ability developed specifically for individuals with SCI to evaluate their performance of activities of daily living (ADL). The SCIM III is composed of 19 items in 3 sub-scales: (a) self-care (6 items, sub-score 0-20); (b) respiration and sphincter management (4 items, sub-score 0-40); and (c) mobility (9 items, sub-score 0-40). The total score ranges from 0 to 100.

The CHART is a 32-item self-report measure of major domains of participation, which has also been utilized extensively by SCI Model System researchers. It assesses functioning in 6 domains of normative role functioning: Physical Independence, Mobility, Occupation, Social Integration, Cognitive Independence, & Economic Self-Sufficiency.

The study physician will rate on a 7-point scale the subject's overall clinical condition following treatment as compared to that at baseline. Scores range from 1 (very much improved) to 7 (very much worse).

Adverse experience(s) will be recorded on the Adverse Event Case Report Form, including the date and time of onset, severity, the relationship to study intervention, the date of resolution, the action taken, and the outcome of the adverse experience. The responsible physician will make a causality assessment for every adverse experience.

Side Effects Record [ Time Frame: Every two weeks for 10 weeks ] [ Designated as safety issue: Yes ]

Participants will be provided a list of side-effects associated with dalfampridine treatment. Three lines marked "other" for open-choice responses will accompany the selection of options for forced-choice side-effects. Participants will rate the severity (visual analog scale [VAS]; 0-100) and frequency ("never", "occasionally", "sometimes", "often" or "always") of side effects for each of the forced and open choice answers. Severity and frequency of side-effects will be rated by participants every 2 weeks during the intervention part of the study.

The purpose of this study is to determine the efficacy, safety, and tolerability of treatment with dalfampridine in combination with locomotor training in persons with chronic, motor incomplete SCI.

Detailed Description

Research suggests that combining therapies could result in important gains in restoring function and improving quality of life in persons with spinal cord injury (SCI). Locomotor training is an activity-dependent rehabilitation therapy that provides repetitive stepping facilitated by manual assistance and body weight support on a treadmill. Recent studies report improvements in walking and standing in individuals with motor incomplete SCI that have undergone intensive standardized locomotor training therapy. Extended release dalfampridine (also known as fampridine or 4-aminopyridine [4-AP]) is a broad spectrum potassium channel blocker that has been shown in animal studies to increase conduction of action potentials in demyelinated axons. Dalfampridine was recently approved by the U.S. Food and Drug Administration (FDA) as a treatment to improve walking in persons with multiple sclerosis (MS). Demyelination is also a prominent feature of incomplete SCI that contributes to the clinical presentation of persons with these injuries.

The purpose of this study is to determine the efficacy, safety, and tolerability of treatment with dalfampridine in combination with locomotor training in persons with chronic, motor incomplete SCI. We hypothesize that persons undergoing combination therapy with dalfampridine and locomotor training will show significantly greater improvements in walking speed and other measures of SCI function than those receiving locomotor training alone.

Able and willing to comply with the study protocol, including availability for all scheduled clinic visits and locomotor training sessions.

Exclusion Criteria:

The participant is a lactating female, or a female of childbearing potential who is sexually active, has not had a hysterectomy or oophorectomy, and is not using an approved birth control method (e.g. tubal ligation, implantable contraception device, oral or injectable contraceptive, barrier method, or sexual activity restricted to vasectomized partner);

The participant has a history of seizures or treatment for seizure disorders;